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To:13038328106 Page:5 of 7 2020-12-01 23:56:54 GMT 13032008630 From:Ben Langenfeld <br /> Pearl Ranch Resource Dect;mbcr 1.2020 <br /> discharge, water quality improvement,shoreline stabilization and wildlife habitat,serving as seclusion,nesting,feeding,and <br /> movement areas,for migratoty birds and mammal species. No mining is planned in the wetland or within a SO;foot buffer: <br /> however.CPW is concerned about the potential draining as a result of the mining. C]"W recommends that the wetland is <br /> monitored frequently for signs of draining or other degradation and if impacted, CPW-recommends that Peak A•faterial s <br /> petforrm wet wu/mitigation by enhancing or creating comparable wetlands elsewhere in the Lower Blue Valley prior to <br /> completion o0he miningproject, <br /> Response <br /> The 1.6-acre wetland area on the northeast corner of the Peak Ranch Resource will be monitored for affect by mining through <br /> a combination of'surface observation and groundwater level monitoring,The ground water level monitoring is achieved <br /> through the piezometers in place between the wetland area and the propose mining area. Furthennore,the wetland is surface <br /> water supported,based on the depth to local groundwater as well as clear surface water inflows via the culverts under CO-9, <br /> Any change to the wetlands will be determined principally by changes in surface water flows from east of CO-9 or front the <br /> Town of Breckenridge drainage easement. <br /> A US Army Corps off-m_ineers wetland delineation is being pursued and will he in place prior to any mining onsite.The <br /> USACL,is the rein of jurisdiction with regards to wetlands,and its determinations and requirements will be followed by <br /> Peak Materials. Wetland mitigation,if needed,will be based on(JSACF permits. <br /> Reclamation <br /> Exhibit l;of the proposal states that the property will be restored to rangeland with a grountAvater•lake_for the benefit elf <br /> local wild1{fe. The proposed 26-acre lake with mar 3:1:slope..s is relatively steep and not ideal far•wildlife. CPW recommends <br /> grading the shoreline of the lake with a diversity ofstopes from of 3:l (minimum)to 3:1,which will balance creating optimal <br /> hah ital.for wildlife and minimizing tweed growth.An ideal pone!for wildlife would he composed of approximately 20-30% <br /> shoal area(4-8.ft deep), which is shallow,enough,for rooted vegetation,provides.for invertebrate production and creates <br /> physical habitat complexity. 'This will allow wildlife to better wilize the lake as habitat and will accommodate fluetztations in <br /> water level. <br /> Resnorrse <br /> Peak Materials will grade the slope ofthe proposed groundwater lakes to be variabic,,with a minimum being 31-H V. Thcsc <br /> shallow slopes will be maintained to 10 fect below the water line at a minimum. <br /> The post mine land use for Peak Ranch Resource is rangeland,not wildlife habitat. Enhancements to the reclamation plant <br /> that improve the quality of life for wildlife will be implemented as lone;as they do not interfere with the successful mining <br /> and reclamation of the site to rangeland with groundwater lakes. <br /> additionally, CPW is concerned that the current proposed depth of the reclamation lake will cause-sirat%cation o j'the water <br /> luvcrs. this may lead toformation ern anoxic hapolimnion concentrated with heavy nivalsfi•om the mining operations,which <br /> could then leach into the gr•ouncftrater that will be feeding the lake. CPW recommends that Peak.Materials modify their <br /> reclamation plan to include a pond design that will avoid potential water quality issues and contour the surrounding,area to <br /> enhance the existing wetlands on the:property.Additionally. CPW recommends rasing a native vegetation seed mix in the <br /> topsoil to enhance winterforage,forr twildlfe. <br /> I2e�ernse <br /> -1 he Peak Ranch Resource lakes(see:figure 1),as groundwater lakes,will see the water within it constantly replaced by <br /> upland flows through the local.aquifer. Its chemistry will be predominated by the incoming groLlndwiitei-flows. Anoxic <br /> hypolimnion occurs mostly in water bodies that are isolated from area groundwater flows(reservoirs,stock ponds,etc.).The <br /> Peak Ranch Resource lakes will not have these conditions. <br /> No heavy metals will be introduced into the Peak Ranch Resource site from offsite sources and the alluvium being mined has <br /> long since finished oxidizing or leaching available metals from the rocks within the deposit.Peak Materials will have a <br /> Response to CPW Comments on Peak Ranch Resource 4 of'6 <br />